IGCSE ICT

• Types of Computer Systems

  • Desktop/Personal Computers
  • Laptop/Notebook Computers
  • Tablet Computers
  • Smartphones
• Hardware


  Tangible physical components of a computer system that you can feel or touch
• Internal Hardware Devices


  • Processor
  • Motherboard
  • RAM & ROM
  • Video & Sound Cards
  • Internal Hard Disk Drives
• External Hardware Devices


  • Monitor
  • Keyboard
  • Mouse
  • Printer
  • External Storage Devices
• Software


  Programs that control computer systems and make the computer do something
• Types of Software


  • Application Software
  • System Software
• Application Software


  Programs that allow the user to do specific tasks
• System Software


  Programs that allow the hardware to run properly and control the computer's hardware and application programs
• CPU


  The central processing unit that performs the processing in a computer system
• Main Components of CPU

  • Control Unit
  • Arithmetic and Logical Unit (ALU)
  • Immediate Access Store (IAS)
• Microprocessor


  A single integrated circuit used instead of a CPU
• RAM


  Random Access Memory, an internal chip where data is stored temporarily
• ROM


  Read Only Memory, memory used to store permanent information
• BIOS


  The boot file in ROM that tells the computer what to do when it first starts
• Input Devices


  • Keyboard
  • Mouse
• Input Devices


  Provide data for processing
• Output Devices


  • Monitor
  • Printer
• Output Devices


  Display the result of processing
• Secondary/Backing Storage


  Stores data/information & programs not being used at the current time
• Backing Store Device


  A reader or recorder, e.g. Hard Disk Drive
• Backing Store Media


  Hardware containing data, e.g. Hard Disk
• Operating System


  Enables users to communicate with computer systems and controls the operation of the computer
• Types of User Interfaces

  • CLI (Command Line Interface)
  • GUI (Graphical User Interface)
• CLI


  Requires typing commands to tell the computer what to do
• GUI


  Uses graphics, icons, menus and a mouse to interact with the computer
• Types of Computers


  • Desktop/Personal Computers
  • Laptop/Notebook Computers
  • Tablet Computers
  • Smartphones
• Desktop/Personal Computers


  • Made up of separate monitor, keyboard, mouse and processing unit
  • Spare parts are standardized resulting in low costs
  • Tend to have better specifications
  • Large casing allows good dissipation of heat build up
• Laptop/Notebook Computers


  • Monitor, keyboard, pointing device and processor are together in a single unit
  • Extremely portable
  • Low weight
  • Low power consumption
  • Processor doesn't generate too much heat
• Tablet Computers


  • Small hand-held devices that can perform many functions of PCs & laptops
  • Often use touch screens to operate
  • On-screen virtual keyboard replaces physical keyboard
• Smartphones


  • Modern phones that can perform similar tasks to other computer systems
  • Main use is for social media & day-to-day planning
  • Smallest, lightest and most portable
• Emerging Technologies


  • Artificial Intelligence (AI)
  • Biometrics
  • Vision Enhancement
  • Robotics
  • Quantum Cryptography
  • Computer Assisted Translation (CAT)
  • 3D & Holographic Imaging
  • Virtual Reality (VR)
• Artificial Intelligence (AI)


  Technology that focuses on creating computer systems that can closely mimic or simulate human intelligence
• Biometrics


  Using a part of a person's body to identify that individual, e.g. fingerprints, retina, iris, face, voice
• Vision Enhancement


  Technology that amplifies visible and infrared light to enhance vision, e.g. LVES and NVE
• Robotics


  Programmed machinery widely used to do physically demanding tasks, either automated or manually operated
• Quantum Cryptography


  Technology that allows messages and data to be sent with complete privacy using advanced encryption based on physics rather than mathematics
• Computer Assisted Translation (CAT)

  When human translators use computer software to help in the translation process
• 3D & Holographic Imaging


  Technology that makes images appear to be 3-dimensional by adding a layer of depth, using 2 regular 2D images manipulated to produce a 3D image
• Virtual Reality (VR)


  When computers create an artificial environment that users can virtually interact with using special equipment like goggles, gloves and headphones
• Input Devices


  • Keyboards
  • Numeric Keypads